Ten years after launching the modular Bolt-Tec and Panel-Tec design silos, Zeppelin significantly steps up production capacities at its Friedrichshafen location. A new automated production line now enables the company to produce the individual segments of these storage and mixer silos more quickly and cost-efficiently.
Worldwide trade has rapidly picked up speed, with a corresponding increase in demand for flexibility. Companies are forced to respond to these changing conditions more and more quickly. Especially the plastics processing industry is faced with challenges such as volatile raw materials costs or meeting recycling quotas. Shortened delivery times are necessary for companies to be able to respond quickly.
In order to avoid cost and risk-intensive heavy-duty transports as well as conventional on-site assembly, Zeppelin started years ago to develop a concept for modular silo construction The prefabricated silo segments can be transported at low cost by ship using standard containers or by road on trucks. Even silos with a storage volume of up to 1,000 m³ can be delivered to their respective point of destination, regardless of the local conditions such as infrastructure or legal regulations regarding road transport. On-site assembly is easy, no specialist crew is required. The advantages of the modular silos are clear: efficiency, flexibility, planning ability, and, due to the easy handling, a high process reliability. An outstanding success - the concept has proved itself around the world
New welding process
But Zeppelin does not stop there: An innovative welding technology makes it possible to produce the individual segments significantly faster and more economically: friction stir welding technology. Up to now, this method has only been used in lightweight construction in the aerospace or automotive industries. Not only is it unique with regard to speed and cost efficiency, but there are also more advantages compared to traditional welding methods. In addition, this procedure further requires no welding additives or inert gas, making consumables redundant. The welding quality is also outstanding and hardly to be achieved with regular methods.
The portal processing plant at the Friedrichshafen Zeppelin location, commissioned one year ago, now enables serial production and thus an automated production process. The portal processing unit for the production of aluminum silo segments is 32 meters long, 13 meters wide and weighs 80 tons.
The production line is fully automated and ensures reproducibility at an extremely high level.
Creating homogeneous compounds
The core of the fully automated process is this ground-breaking welding technology. Here, a rotating, hard-wearing tool is pressed into the joint gap between two clamped work pieces. The friction between the tool and the work piece causes the material to heat up and the aluminum is plasticized without reaching the melting point. The material compacts during cooling, leaving a homogeneous and high-strength weld seam.
In addition, the new welding process proves its worth through its high seam strength, welding seams flush with the metal surface and a low welding distortion. This is due to the reduced heat input. This process does not require a liquid weld pool, which prevents seam faults typical for aluminum such as pores or solidification cracks.
This procedure is further easier on the workers and also safer due since no toxic fumes arise. The environmental impact is also significantly lower.
Flexibility on the construction site
This system comes with a number of advantages when it is later installed on the operation site. First, there are the reduced freight charges. The silo parts can be transported on standard trucks or 40-foot containers. Afterwards, local staff assemble the silo parts on site with screw connection. Weather is no longer an issue, because no additional welding is necessary. The silo may even be installed inside a building. The modular construction even enables a later capacity increase of the silo without time-consuming welding on site.
Looking into the future
With Zeppelin’s entry into silo serial production, the company not only expects distinct competitive advantages on distant markets but also a significant order increase in Europe. After only one year, the company is working a three-shift production line operation. For one, this investment in serial production shows our clear commitment to the Friedrichshafen location and its employees. It also meets the elevated demands of our customers.
Author: Michael Häring
The author is Vice President Sales Products at Zeppelin Systems, Friedrichshafen.